Means of the type mentioned above are used in the rehabilitation of pipelines, in particular of main pipelines and branch pipelines, in the area of the sewerage system. By inserting such means, leaking and defective sections of pipelines, and in particular of pipeline joint portions, can be rehabilitated. In this case, the means can be configured as a lining element and/or as a calibrating tube.
A means configured as a calibrating tube of the type mentioned above has a main pipe section or main pipe calibrating tube and a branch pipeline section or branch pipeline calibrating tube, which are configured to be expansible and inflatable. In the inflated state, the calibrating tube has the approximate size and shape of the pipe section to be rehabilitated. Furthermore, the branch pipe calibrating tube is disposed at an angle to the main pipe calibrating tube, with this angle matching the angle between the house connection pipe and a main pipe. In order to rehabilitate the mouth region, the calibrating tube is pushed onto a device for rehabilitating the pipelines, which is also referred to as a packer. In the process, the calibrating tube is fastened at each end to the packer by means of clamping collars, so that an air-tight connection is produced. Furthermore, a resin-impregnated lining element is provided. Then, the branch pipe calibrating tube is inverted into the main pipe calibrating tube together with the liner. For this purpose, the free end of the branch pipe calibrating tube is provided with a rope. At the same time, the air in the main pipe calibrating tube and in the branch pipe calibrating tube is suctioned off. Then, the packer is moved to the mouth region to be rehabilitated. Subsequent to positioning, the main pipe calibrating tube is inflated and the branch pipe calibrating tube with the liner is inverted, i.e. folded over, into the house connection. Inversion is carried out using a rope or cable pulling device attached to the outside of the free end of the branch pipe calibrating tube. As a consequence of the inversion, the lining element is pressed against the site to be rehabilitated. After the liner has hardened, the air is let out of the calibrating tube, and the device is moved out of the main pipe. The hardened lining element then rests against the inner wall of the pipeline with a substance-to-substance connection.
A means of the type mentioned in the introduction, which is configured as a lining element and can also be referred to as a liner, comprises a substrate layer of resin-absorbing material, in particular a non-woven or fiber material. Prior to the insertion of the lining element, the layer consisting of the resin-absorbing material is impregnated with the resin, and then the lining element is brought by means of a rehabilitation device, which can also be referred to as a packer, into its final position at the site to be rehabilitated. The above-described inversion process, or also eversion process, is then used for pressing on the lining element. A calibrating tube as described above can be used for pressing the lining element against the inner pipe wall. Moreover, the lining element can be pressed against the inner pipe wall also without using a calibrating tube. After the resin has hardened, the lining element rests against the inner pipe wall with a substance-to-substance connection.
Hardening takes place by charging the means with a medium, in particular hot vapor, in order to trigger the external reaction process of the resin. For an optimal installation result, it is necessary to detect and evaluate the pressure required for pressing and/or the temperature required for hardening the resin, in order to increase or reduce the temperature and/or the increase or reduce the pressure, if necessary. In order to detect the above-mentioned physical parameters, it is known to provide the means with a sensor.
For example, a lining element is shown in U.S. Pat. No. 6,942,426 B1, which is provided with a plurality of temperature feelers that measure the temperature at the interface between the outer face of the lining element and the inner face of the pipe wall during hardening in order thus to determine the hardening temperature.
Furthermore, it is known from WO 2014/022097 A1 to provide the lining element with a transmitter comprising an RFID chip and a sensor. Among other things, the pressure and temperature during the hardening process can be measured by means of the sensor. In this case, the transmitter is applied to the lining element in such a way that it rests on the interface between the outer face of the lining element and the inner face of the pipe.
The lining element or sensors used for measuring pressure and temperature known from the prior art are contact-sensitive sensors. Thus, a contact between the lining element and the inner pipe wall is always required for the measurements. Consequently, the temperature and the pressure for hardening the medium are measured only on the outer face of the lining element. Thus, the temperature and the pressure of the medium used for hardening can only be determined indirectly. Consequently, the exact adjustment of the physical parameters of the medium is made difficult. In addition, the sensors remain in the pipeline to be rehabilitated after hardening, and therefore cannot be reused.